The stakes could not be higher. After two days of being rigorously tested on their entire schooling since kindergarten, one third of the students will be excluded from university and a white-collar future.

A Chinese saying compares the exam to “the stampede of 10,000 horses trying to cross a single log bridge”.

Each year there are suicides before and during the exams and June is known by Chinese teenagers as the “black” month. Students joke that the strain of the exam is enough to make you “shed your skin in exhaustion”.

Across China, parents visited local temples to burn incense and pray, while security officers sniffed out potential cheats. Already, more than 60 people have been arrested for selling wireless headsets and other electronic gadgets to desperate students.

The stress of taking the university entrance exam, or gao kao in Chinese, is so great that this year some schools have hired psychologists to offer therapy, while others have organised pillow fights, balloon-bursting sessions and even limbo dancing to try to relax students who typically have cramming classes from early morning to as late as 10.30pm.

Local governments have calmed construction sites at night to allow students to rest properly.

The questions in the exam can also be baffling. Last year, students were invited to write an 800-word essay on the question: “Why chase mice when there are fish to eat?” Another question asked: “What is light reading?”

In Sichuan province, 44-year-old Liang Shi sat the exam for the 15th time, much to the embarrassment of his 18-year-old son who was also being tested.

Mr Liang, who owns a construction supplies business, said he refused to accept defeat in the exam, and could not live with the bitterness of failure. “I feel like it is a hot brand, scarring me,” he said.

However, upon completing his papers for the day, he said he had not done well. “I think I managed to mess it up again, especially the mathematics paper,” he said. “I just want to fulfil my dream of going to university,” he said. “But this exam, it is like I want to heat some water, and I keep adding wood, but it just never boils”.